Automated component creation for legacy C++ and fortran codes.

A significant amount of work has been spent creating component models and programming environments, but little support exists for automation in the process of creating components from existing codes. To entice users to adopt the component-based paradigm over traditional programming models, integration of legacy codes must be as simple and fast as possible, We present a system for automating the IDL generation stage of component development based on source code analysis of legacy C, C-t-4 and Fortran codes using the Program Database Toolkit. Together with IDL compilation tools such as Babel, we provide an alternative to hand-written IDL code for legacy applications and libraries. In addition to generating IDL, we propose an XML-based method for specifying meta-data related to type mapping and wrapper generation that can be shared between our tools and IDL compilers. The component model of choice for this work is the Common Component Architecture (CCA) using the Scientific Interface Definition Language (SIDL), though the concepts presented can be applied to other models

An Image-Free Opto-Mechanical System for Creating Virtual Environments and Imaging Neuronal Activity in Freely Moving Caenorhabditis elegans

Non-invasive recording in untethered animals is arguably the ultimate step in the analysis of neuronal function, but such recordings remain elusive. To address this problem, we devised a system that tracks neuron-sized fluorescent targets in real time. The system can be used to create virtual environments by optogenetic activation of sensory neurons, or to image activity in identified neurons at high magnification. By recording activity in neurons of freely moving C. elegans, we tested the long-standing hypothesis that forward and reverse locomotion are generated by distinct neuronal circuits. Surprisingly, we found motor neurons that are active during both types of locomotion, suggesting a new model of locomotion control in C. elegans. These results emphasize the importance of recording neuronal activity in freely moving animals and significantly expand the potential of imaging techniques by providing a mean to stabilize fluorescent targets